Precision Pesticide Delivery Based on Aerial Spectral Imaging

A prototype sprayer to deliver pesticides based on an aerial scan of a Nova Scotia blueberry field was developed and analysed. A program written in C reads the position from a GPS receiver and correlates it with a GIS file containing spraying information. GIS software used to create the files is generally ArcGIS software from ESRI but the program is also capable of reading a file from Idrisi Kilimanjaro from Clark’s lab. The program finds and inspects all pixels under a nozzle spray during one second of travel based on the previous direction and speed of travel. The sprayer nozzles are turned on and off using solenoid valves. The solenoid valves and the GPS system use a 12 volt power supply so the entire system can be operated on a vehicle electrical system. The system is sensitive to positional error. Preliminary results using an off-the-shelf low cost receiver were positive. The presence of hills or the proximity to tree lines will cause positional error, which will reduce the accuracy of the system. The GPS receiver is a John Deere Starfire and with the SF2 differential signal has an accuracy of plus or minus 10 cm. The pixel resolution is roughly 1 meter.